Multi-target strategy to address Alzheimer’s disease: Design, synthesis and biological evaluation of new tacrine-based dimers
摘要:
The multifactorial nature of Alzheimer's disease (AD) offers us a textbook example where parental compounds, mostly marketed, are modified with the aim of improving and/or conferring two or even more biological activities to contrast or less frequently revert the disease's symptoms. This is the case of tacrine and its dimeric derivative bis(7)-tacrine which, for instance, paved the way for the development of a broad collection of very interesting homo- and heterodimeric structures, conceived in light of the emerging multi-target approach for AD-related drug discovery. As a contribution to the topic, we report here the design, synthesis and biological evaluation of 12 compounds referable to bis(7)-tacrine. In addition to the cholinesterase activity, some of the selected compounds (7-9 and 12) were capable of inhibiting the non-enzymatic function of AChE and/or showed a remarkable activity against BACE1. Thus, the present study outlines a series of newly synthesized molecules, structurally related to bis(7)-tacrine, endowed with extended biological profile in agreement with the emerging multi-target paradigm. (C) 2011 Elsevier Masson SAS. All rights reserved.
AbstractAn efficient C–C bond coupling reactions (Suzuki–Miyaura and Glaser) catalyzed by PdO/GO nano-catalyst is presented. In addition, PdO/MWCNT nano-catalyst-mediated domino one-pot synthesis of 2-alkyl/2-aryl benzofurans has been accomplished from 2-iodophenols and terminal alkynes. The formation of benzofurans proceeds through intermolecular Sonogashira reaction followed by intramolecular nucleophilic
The first example of sole direct C–H bond arylation of benzo[b]furans with aryl chlorides was achieved catalyzed by a well-defined NHC-Pd(II)-Im complex. Under the suitable conditions, all reactions involving kinds of benzo[b]furans and (hetero)aryl chlorides proceeded well to give the desired C2-arylated benzo[b]furans in sole regioselectivity in acceptable to high yields, providing an efficient and
明确定义的NHC-Pd(II)-Im络合物催化了苯并[ b ]呋喃与芳基氯的唯一直接C-H键芳基化反应。在合适的条件下,所有涉及各种苯并[ b ]呋喃和(杂)芳基氯化物的反应均能顺利进行,从而以唯一的区域选择性提供所需的C2-芳基化苯并[ b ]呋喃,并以高收率接受,从而提供了有效而经济的途径用于苯并[ b ]呋喃的直接C2-H键芳基化。
Recyclable Pd/CuFe<sub>2</sub>O<sub>4</sub> nanowires: a highly active catalyst for C–C couplings and synthesis of benzofuran derivatives
Efficient heterogeneous Pd/CuFe2O4 nanowires which catalyze cross coupling transformations are described. The protocol is applied to a one-pot synthesis of benzofurans via Sonogashira coupling and an intramolecular etherification sequence.
was established to be a crucial parameter for this transformation. When combined with DoM and traditional Pd-catalyzed Suzuki-Miyaura strategies, the methodology offers concise routes to uniquely substituted molecules, avoiding the need for protection/deprotection of the phenol and the use of strongly nucleophilic cross-coupling partners.
Visible light mediated desilylative C(sp<sup>2</sup>)–C(sp<sup>2</sup>) cross-coupling reactions of arylsilanes with aryldiazonium salts under Au(<scp>i</scp>)/Au(<scp>iii</scp>) catalysis
作者:Indradweep Chakrabarty、Manjur O. Akram、Suprakash Biswas、Nitin T. Patil
DOI:10.1039/c8cc03925a
日期:——
Desilylative C(sp2)–C(sp2) cross-coupling reactions of arylsilanes with aryldiazonium salts under Au(I)/photoredox catalysis have been reported. The addition of Cu-salts as catalysts was found to be crucial for the success of this transformation.